1. Field of the Invention
The invention relates in general to a search method for a wireless communication system, and more particularly to a search method for finding a target location in a variable space so that an output result of a wireless communication system satisfies a target value.
2. Description of the Related Art
A communication system frequently encounters optimization issues. For example, an image rejection mixer needs to adjust a size and a phase of a local signal to remove a signal of an image channel, i.e., to minimize signal energy of the image channel. In a radio-frequency identification (RFID) application, a carrier signal transmitted from a reader becomes noise due to reflection, and the noise may then be received by the reader. The energy of such noise also needs to be minimized.
To achieve optimization, a most appropriate value for a controllable variable is sought for in order to render a maximized or minimized output result. The search process may be accomplished through algorithms. For example, exhaustive search is a type of algorithm that tries all possible variable combinations of a variable once. According to all output results generated by the combinations, an optimal output result can be identified, and thus the most appropriate values for the variable can be obtained. However, as each of the variable combinations needs to be executed once, the exhaustive search process for finding the most appropriate variable values is not only extremely time-consuming but also involves an immense amount of computations. Therefore, the conventional exhaustive search is impractical for a communication system that demands high-speed and power-saving features.